Look, you have my sympathy, but I literally just raised the example of the Chinese communist movement, where nearly 95% of the cadres were murdered by the KMT or perished during the Long March, which also involved trekking thousands of miles of arduous mountainous terrains to escape from the nationalist persecution.

I'll reflect on this, but currently the argument doesn't convince me. The Chinese communist movement didn't just decide one day to raise an army out of the blue. The fact that there was an ongoing armed conflict on Chinese soil was what allowed them to do that. Cities were being laid to waste. Villages were being burned. That makes it easier to recruit people to die, because 1) the country is already actively under contest, there is a vacuum to be fought over, so people can imagine victory even if the road is difficult, even if battles are lost along the way, 2) violence is already killing huge numbers of people, so it is not a choice between "risk death and join us, or remain in your city and enjoy certain peace," and in fact there are already many millions of people displaced from their homes who have nothing to lose but the clothes on their backs, and millions more people who fear it happening to them in the immediate future, because there is a climate of extreme and immediate uncertainty, and 3) because of the first two reasons, an ordinary person sees that it is credible for an armed movement to grow and successfully recruit other people under current conditions, and they see that other people see it too, which means that if they join the movement they might not be alone in joining it, which removes the "first wildebeest into the river" hesitation that arises in peacetime. The situation has reached a quorum for collective action where people recognize that if they act others may join them.